Blood Transfusions Can Change Your Blood Type

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We present two leukemia patients whose blood group changed during the course of their treatment. 

The first case was a 17-y-old boy with acute myeloid leukemia (AML) whose blood group at presentation was O Rhesus positive (O Rh + ve). After 2 cycles of induction chemotherapy his disease was in remission, however, his blood group changed to A Rh + ve. He subsequently received A Rh + ve blood products without any transfusion reactions. The patient continues to be in remission and his blood group still remains A Rh + ve.

The second case was an 11-y-old boy with acute lymphoblastic leukemia (ALL) whose blood group at presentation in March 2011 was B Rh negative (B Rh-ve). However, his blood group changed to B Rh + ve when he relapsed in May 2015, only to revert back a month later to B Rh-ve after he attained remission with chemotherapy. The patient’s blood group changed back to B Rh + ve after 2 mo in August 2015 when his disease relapsed again. In both the cases the patients’ blood groups were determined by their disease remission status.